"The rocks have not only proven to be largely impervious to nature, but also now appear to be withstanding the effect of nearby heavy industry," says geologist Professor Brad Pillans of the Australian National University in Canberra.

Pillans will present the results of a study of beryllium isotopes in the rocks that give insight into how slowly the rocks have been eroding due to natural causes.

He says his findings provide an important baseline for other studies looking at the impacts of industry.

"The erosion rates turn out to be very low indeed by world standards," says Pillans, whose work was partly funded by Woodside Energy.

He says the surface of the rock is eroding at between 0.2 and 1.5 millimetres per thousand years.

"The rock art can survive for up to 50,000 years at those rates," says Pillans.

He says the natural erosion rate is so low because the rocks are very hard and there is less than 250 millimetres of rain in the area per year in the area.

"It's the perfect canvas chosen by the Aboriginal people for the long term existence of their art," says Pillans.

Industry effects

Pillans says the rocks have a dark chemical coating, made up mainly of iron oxides, that provides a strong colour contrast to the paler interior of the rock into which the carvings are made.

"These thin oxide layers are so inert that any extra industrial emissions would have limited effect," he says.